The present invention relates to novel fuel additive and fuel formulations. These composition are effective in reducing intake valve deposits and do not contribute to increased combustion chamber deposits in port fuel injected engines. In particular, the present invention relates to novel fuel additives for use in gasoline formulations.
It is well known to those skilled in the art that internal combustion engines form deposits on the surface of engine components, such as carburetor ports, throttle bodies, fuel injectors, intake ports, and intake valves, due to the oxidation and polymerization of hydrocarbon fuel. Deposits also form in the combustion chamber of an internal combustion engine as a result of incomplete combustion of the mixture of air, fuel, and oil. These deposits, even when present in relatively minor amounts, often cause noticeable driving problems, such as stalling and poor acceleration. Moreover, engine deposits can significantly increase an automobile's fuel consumption and production of exhaust pollutants. Specifically, when the gasoline used in a given engine is of a constant octane number, the power output decreases when deposits are formed. In order to maintain the power output at a predetermined desired level, it then becomes necessary to increase the octane number of the fuel over the course of time. This Octane Requirement Increase (ORI) is undesirable. Therefore, the development of effective fuel detergents or deposit control additives to prevent or control such deposits is of considerable importance, and numerous attempts have been made to identify suitable compositions. The present invention is directed to novel compositions which have not only demonstrated unexpected and synergistic improvement in the control of intake valve deposits (IVD) compared to other formulations but also do not cause any significant increase in combustion chamber deposits.
U.S. Pat. No. 4,332,595, Herbstman et al., Jun. 1, 1982, discloses a compound having the formula EQU R--[O--CH.sub.2 --CH(CH.sub.3)].sub.y --NH--(CH.sub.2).sub.3 --NH.sub.2
where R is hydrocarbyl radical having from 8 to 18 carbon atoms and y is about 2 to 6.
U.S. Pat. No. 5,089,029, Hashimoto et al., discloses a fuel additive composition which comprises an additive compound having the formula EQU R--O--(AO).sub.m --(C.sub.3 H.sub.6 N).sub.n H
wherein R is a hydrocarbyl radical having 10 to 50 carbon atoms, A is an alkylene group having 2 to 6 carbon atoms, m is an integer of 10 to 50 and n is an integer of 1 to 3; and 0.05 to 20 parts by weight, per 1 part of said additive compound, of a mineral or synthetic oil. This patent also claims a fuel oil composition comprising a fuel oil, 1 to 20,000 ppm of the above additive compound, and 0.05 to 20 parts by weight, per 1 part of said additive compound, of a mineral or synthetic oil. The mineral or synthetic oil is preferably selected from the group consisting of poly-alpha-olefin, polybutene, an adduct of an alcohol with an alkylene oxide, an adduct of an alkylphenol with an alkylene oxide, an alkylene oxide polymer such as an addition product of propylene oxide or butylene oxide and an ester thereof.
U.S. Pat. No. 5,264,006, Schilowitz et al., Nov. 23, 1993, discloses distillate fuel compositions containing an alkyl ether monoamine having the formula EQU RO[C.sub.4 H.sub.8 O].sub.(9-18) CH.sub.2 CH.sub.2 CH.sub.2 NH.sub.2
where R is highly branched alkyl group derived from a Guerbet alcohol containing between 12 and 40 carbon atoms, are effective in reducing the formation of intake valve deposits in internal combustion engines.